An EC motor of this kind having a three-phase stator and an armature designed as a rotor is known in the field. It has a position-measuring device for recording the position of the armature poles in relation to the phases of the winding, which, for each phase, has a Hall-effect sensor that is hardwired to the stator, in response to a relative motion between the stator and the rotor, the Hall-effect sensor being magnetized by the magnetic field of the rotor pole moving past it at the particular moment. In this context, the rotor poles function as an encoder, which, in each of the Hall sensors, generates a magnetic field and thus a Hall voltage which can be used as a position-measurement signal. The measurement-signal outputs of the Hall sensors are linked to a driving device, which, via an output stage, supplies current to the individual phases of the winding in such a way that, between the stator and the rotor, a traveling magnetic field forms that drives the rotor. To achieve a smoothest possible operation and a high torque in such an electronically commutated electric motor, the measurement signals used to commutate the electric motor must reproduce the position of the magnetic poles in relation to the phase in question as accurately as possible.
When the EC motor is manufactured, the actual electric motor, made up of the stator and the rotor, is first fabricated and assembled. The position sensors are subsequently positioned on the stator and electrically connected to the driving device. In particular, when the motor and the Hall sensors are purchased from different manufacturers, positioning errors can occur when positioning the Hall sensors on the stator. This can lead to the measurement signal from several, many, or all of the Hall sensors deviating from the actual position of the rotor relative to the phase assigned to the Hall sensor. To reduce positioning errors of this kind, known methods heretofore provide for making an additional mechanical adjustment of the Hall sensors at the end of the production line. However, this entails a considerable outlay for manufacturing. It is also disadvantageous that the EC motor must be designed in such a way that the Hall sensors are still movable relatively to the stator at the end of the production lines.